Well. looks like squid using heuristics after all:
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(291) refreshCheck: checking freshness of 'http://mydomain.zone/1.txt'
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(312) refreshCheck: Matched '<none> 0 20%% 259200'
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(314) refreshCheck: age: 65955
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(316) refreshCheck: check_time: Fri, 01 Sep 2017 11:49:12 GMT
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(318) refreshCheck: entry->timestamp: Thu, 31 Aug 2017 17:29:57 GMT
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(179) refreshStaleness: No explicit expiry given, using heuristics to determine freshness
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(198) refreshStaleness: Last modified 5524975 sec before we cached it, L-M factor 20.00% = 1104995 sec freshness lifetime
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(205) refreshStaleness: FRESH: age 65955 <= stale_age 1104995
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(338) refreshCheck: Staleness = -1
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(461) refreshCheck: Object isn't stale..
2017/09/01 14:49:12.296 kid2| 22,3| refresh.cc(470) refreshCheck: returning FRESH_LMFACTOR_RULE
It's a shame there's no warning header, like "https://tools.ietf.org/html/rfc7234#section-5.5.4" suggests.
Guess, I need to set refresh_pattern's max option to minimal value.
On Thu, Aug 31, 2017 at 8:26 PM, Alexander Lazarev <gummeah@xxxxxxxxx> wrote:
Thank you for reply!I still don't understand what's happening.I create file 1.txt with a little bit of text data. Request it with curl. Web-server returns it without any cache related headers to squid, squid returns it to me. Getting it with curl one more time, squid serves it straight from cache without validation(no entries in log on origin server).I create one more file 2.txt with some data. Do same things, same headers in response. Second response from squid is from cache but validated from origin server(i see 304 in origin server logs).What could be wrong?I have thought maybe squid applying heuristic freshness, but i didn't see any warnings in headers.Maybe some sort of a bug?On Fri, Aug 25, 2017 at 6:18 PM, Amos Jeffries <squid3@xxxxxxxxxxxxx> wrote:On 26/08/17 00:37, Alexander Lazarev wrote:
Hello guys!
I'm using squid as a reverse-proxy. And I can't understand how squid decides when to check for fresh version of file from origin server.
It looks like for some documents it sends 'If-Modified-Since' or similar headers and if it gets 304, it serves file from cache. And for some documents it doesn't check for fresh version and always serves from cache. > I was testing that with curl without any additional headers.
Can some explain how that works or where I can read about that in detail?
The HTTP specification RFC 723x series was re-written to be a lot more easily understood, so those are probably the best place to read up about it.
The features you are asking about are covered in:
Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests
<https://tools.ietf.org/html/rfc7232 >
Hypertext Transfer Protocol (HTTP/1.1): Caching
<https://tools.ietf.org/html/rfc7234 >
And is it possible to make squid always check for fresh version before serving from cache?
It does when needed. The situation may be clearer after reading the above.
Amos
_______________________________________________
squid-users mailing list
squid-users@lists.squid-cache.org
http://lists.squid-cache.org/listinfo/squid-users
_______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users
